The objective of this investigation is to analyze, assign and clarify the controversial roles of creep and corrosion in the marginal breakdown of dental amalgams of conventional chemistry. The methodology will involve the determination of the creep and corrosion behavior of dental amalgams as a function of the nature and volume fractions of various microstructural phases with special emphasis on the ratios of gamma 1/gamma 2 and gamma 1/gamma 2 plus CuSn in the matrix of amalgams fabricated from alloys of known chemical composition and processing history. Creep data as a function of stress and temperature will be obtained with a creep tester. Corrosion data will be obtained using potentiostatic anodic polarization techniques. Microstructural characterization will be carried out using optical microscopy, scanning electron microscopy, x-ray diffraction analysis and electron probe microanalysis. The results will be interpreted in terms of the creep and corrosion behavior of the individual phases, singly and in combination. Conclusions will be made regarding specific relationships between microstructure and creep and corrosion. It is anticipated that a relevant predictive parameter for the marginal breakdown of dental amalgams will be established.